.site-demo-button div{
    margin: 5px 5px 10px;
}
.layui-form-label{
    width: 90px;
}
.huan_a{
    height: 20px;
}
.huan_center{
    text-align:center;
}
element.style{
    height: 300px;
}
.layui-input-block{
    margin-left: 0;
}